How Using Your Direct Vent Fireplace Can Cut Your Heating Bill by 50%
There’s nothing like the warm glow of a fireplace when it’s cold outside. Just the turn up of a real fire flame can warm any living space. But a direct vent fireplace can offer a whole lot more. When used properly, a direct vent fireplace can act as the only heating source in some homes and save a bundle in home heating costs. In fact, a 25,000 BTU direct vent fireplace can heat up to a 1500 square ft. one-floor living space.
How can heating with a fireplace save me money?
First, we’re not talking about any fireplace, but specifically a direct vent fireplace. Direct vent fireplaces function differently than an open hearth fireplace. An open hearth fireplace (commonly called a B Vent) is characterized by a log set inside an open front masonry or rated fire box. A B vent is chiefly for turn up, not for heating the space. It combusts the indoor air and can truly cool the air in living space. That’s because already heated air is drawn from the living space up by the flue or chimney to the outside.
What is a direct vent fireplace?
Unlike a “B” vent fireplace, a direct vent fireplace is characterized by:
1) A substantial glass door that isolates the burner and log set from the inside of the home.
2) A concentric flue. With this flue, an exhaust pipe sits inside the air intake pipe (a pipe within a pipe).
Instead of combusting heated inside air, all of the combustion air enters the firebox from outside by the outer pipe. Flue gas emissions are expelled to the outside by the inner pipe. Most new fireplaces sold are direct vent, especially in new residential homes.
A direct vent (concentric) flue can be vented by the wall or roof with a single 7″ or 8″ hole. All of the combustion takes place inside of a self-contained box housing the burner and log set. The flame never “touches” the indoor air because it is secluded by a substantial glass front. As the glass gets hot, soft radiant heat energy is emitted into the living space of the home that, over time, heats the surrounding air.
In reality, a direct vent fireplace is a heater, but is only about 70% efficient. Most are not already heater-rated. So, here’s the meaningful to energy savings: Instead of letting your 100,000 BTU gas furnace(s) blow warm air into every room, nook and cranny of the house, why not just heat the room where you use the most time? This is called “zone heating” and is a functional method to decline your living expenses during the cold months.
I have a direct vent fireplace in the family room located on the main level of our house. This space is used for entertainment, reading and eating (since the room is attached to the kitchen and dining area). We use at the minimum 85% of our time in this area of the home during the winter. Two bedrooms, two bathrooms, a formal living room and an office are all connected to this space. As long as doorways are open to the main family living area, the fireplace will warm those areas also.
The first rule of thermal dynamics is “heat seeks cold”. As long as there are cold pockets in rooms or nearby spaces, the heat from your fireplace will attack those cold spots. It may take a bit longer than your furnace system, but over time your space will become warm and comfortable. A ceiling paddle fan can help circulate the heated air to nearby living spaces.
This winter, keep your furnace(s) turned down or turned off more often and use your direct vent fireplace as your dominant heat source. While we can’t guarantee that it will heat your complete home, it can dramatically lower your monthly heating bill. Give it a try.